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arXiv · 1111.2103

AGN obscuration through dusty infrared dominated flows. II. Multidimensional, radiation-hydrodynamics modeling

A. Dorodnitsyn·T. Kallman·G. S. Bisnovatyi-Kogan
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Abstract

We explore a detailed model in which the active galactic nucleus (AGN) obscuration results from the extinction of AGN radiation in a global flow driven by the pressure of infrared radiation on dust grains. We assume that external illumination by UV and soft X-rays of the dusty gas located at approximately 1pc away from the supermassive black hole is followed by a conversion of such radiation into IR. Using 2.5D, time-dependent radiation hydrodynamics simulations in a flux-limited diffusion approximation we find that the external illumination can support a geometrically thick obscuration via outflows driven by infrared radiation pressure in AGN with luminosities greater than $0.05\, L_{\rm edd}$ and Compton optical depth, $\tau_{\rm T}\gtrsim 1$.

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A. Dorodnitsyn, T. Kallman, G. S. Bisnovatyi-Kogan. 2011-11-09. AGN obscuration through dusty infrared dominated flows. II. Multidimensional, radiation-hydrodynamics modeling. https://doi.org/10.1088/0004-637x/747/1/8

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